BACKGROUND Plant-derived biomass is a potential alternative to fossil feedstocks for a greener economy. Enzymatic saccharification of biomass has been studied extensively and endoglucanases have been found to be a prerequisite for quick initial liquefaction of biomass under industrial conditions. Pichia pastoris, widely used for heterologous protein expression, can be utilized for fungal endogl...

BACKGROUND Thermostable enzymes have several benefits in lignocellulose processing. In particular, they potentially allow the use of increased substrate concentrations (because the substrate viscosity decreases as the temperature increases), resulting in improved product yields and reduced capital and processing costs. A short pre-hydrolysis step at an elevated temperature using thermostable en...

BACKGROUND Enzymes still comprise a major part of ethanol production costs from lignocellulose raw materials. Irreversible binding of enzymes to the residual substrate prevents their reuse and no efficient methods for recycling of enzymes have so far been presented. Cellulases without a carbohydrate-binding module (CBM) have been found to act efficiently at high substrate consistencies and to r...

Thermoascus aurantiacus xylanase is a thermostable enzyme which hydrolyses xylan, a major hemicellulose component of the biosphere. The crystal structure of this F/10 family xylanase, which has a triosephosphate isomerase (TIM) barrel (beta/alpha)(8) fold, has been solved to small-molecule accuracy at atomic resolution (1.11 A) at 293 K (RTUX) and at ultrahigh resolution (0.89 A) at 100 K (CTUX...

In addition to the most recently reported aerobic anoxygenic phototrophic bacterium Chloroacidobacterium thermophilium [1], five phyla of phototrophic bacteria have been reported, including four phyla anoxygenic phototrophic bacteria (anaerobic and aerobic anoxygenic phototrophic Proteobacteria, filamentous anoxygenic phototrophs (FAPs), green sulfur bacteria and heliobacteria) and oxygenic pho...

Detergent extracts of cell envelopes of the gliding bacterium Herpetosiphon aurantiacus formed channels in lipid bilayers. Fast protein liquid chromatography across a HiTrap-Q cation-exchange column demonstrated that a 45-kDa protein forms the channel. The observation of a channel-forming protein suggests that Herpetosiphon aurantiacus Hp a2 has a permeability barrier on its surface.

BACKGROUND Enzyme end-product inhibition is a major challenge in the hydrolysis of lignocellulose at a high dry matter consistency. β-glucosidases (BGs) hydrolyze cellobiose into two molecules of glucose, thereby relieving the product inhibition of cellobiohydrolases (CBHs). However, BG inhibition by glucose will eventually lead to the accumulation of cellobiose and the inhibition of CBHs. Ther...

BACKGROUND Lytic polysaccharide monooxygenase (LPMO) is a group of recently identified proteins that catalyze oxidative cleavage of the glycosidic linkages of cellulose and other polysaccharides. By utilizing the oxidative mode of action, LPMOs are able to enhance the efficiency of cellulase in the hydrolysis of cellulose. Particularly, auxiliary activity family 9 (AA9) is a group of fungal LPM...

BACKGROUND As a green alternative for the production of transportation fuels, the enzymatic hydrolysis of lignocellulose and subsequent fermentation to ethanol are being intensively researched. To be economically feasible, the hydrolysis of lignocellulose must be conducted at a high concentration of solids, which results in high concentrations of hydrolysis end-products, cellobiose and glucose,...